President Abdel Fattah al-Sisi, who is seeking re-election in March, ordered the armed forces in November to defeat militants within three months after an attack on a mosque killed more than 300 people, the deadliest such incident in the Arab world's most populous country.

The military statement earlier on Sunday said forces involved in the operation had found a media centre with computers, communication equipment and books and documents related to jihadist ideology.

Security forces also uncovered and destroyed six farms used to grow banned narcotics, the statement said. The mission, announced Friday, is meant to target "terrorist and criminal elements and organizations" across Egypt.

Egypt's armed forces Saturday continued what it describes as "intensive airstrikes against terrorist targets and gatherings" in Central and North Sinai.

Egypt's security forces have been increasingly targeted by extremists since the army in 2013 overthrew Mr El Sisi's predecessor, president Mohammed Morsi.

Most terrorist attacks carried out in North Sinai in recent years have been claimed by the Daesh-affiliated Ansar Beit al-Maqdis.

And last September Sissi met Netanyahu for the first time in public, the encounter coming ahead of the United Nations General Assembly in NY. It covers north and central Sinai, the Nile Delta and the Western Desert along the porous border with Libya.

Its second and third phases began in January and April 2016, respectively, while the fourth phase started In August 2017, 10 days after 26 Egyptian security personnel were killed in an attack the North Sinai city of Rafah.